In the past there have been numerous types of tools which have been proposed for use in removing freon from a can. This invention, generally, is of such a tool which is improved as is set forth more fully hereinafter and which is composed of a bifurcated socket defining member adapted to be nested about a can and wherein there are extending legs and a centrally located piercing element which includes a valve so that, when the legs are squeezed toward one another and a can is positioned in the socket, the piercing element will pierce the can to permit the freon to flow through the valve and piercing element to a tube connected to an automobile air conditioning system.
In the preferred embodiment, the device includes a one-way check valve so that in the event someone inadvertently attaches the hose to the high pressure side of the compressor, the pressure will be contained at the valve. It will not enter the can. Also, the valve is aimed away from the operator when the tool is being attached to the can. Preferably, the product is of a tough durable plastic which is impervious to cold or heat, such as that which is commercially available and known as Delrin, a product of the E. I. duPont Company. The check ball is preferably of stainless steel and the valve core is of brass and stainless steel, the valve barrel being of brass. The needle is hardened steel preferably with nickel plating so that it will not rust. The device is adapted for rapid charging of a system in relation to conventional can tap valves. In operation, to charge a system, a low pressure hose is connected to the fitting of the tool to depress the Schrader valve. A conventional size freon can, such as the often encountered 25/8 inch diameter can is positioned as shown in the drawings within the tool. The tool is biased closed and it will puncture the can. When the manifold valve is opened, it does not have to be closed until the system is charged because of the check valve included in the device. This check valve prevents freon from leaking back through the tool. When the can is empty, the handles are opened and another can may be inserted and this process continued until the system is charged. Thereafter, the manifold valve is closed and a partially used can may be left in the charging line or unscrewed from the line. It will not leak the remaining portion of freon from the can.